1. Field of the Invention
This invention relates to a water-closet or toilet equipment, and in particular, it relates to the providing of one particular part of the apparatus which comprises such equipment, namely, the particular part or member which is located within the flush tank in the vicinity of its bottom and engages, with a bottom portion of said part, the opening or conduit (usually a member which is, in outline, generally cylindrical) through which water contained in the flush tank is permitted to pass by gravitational flow to the bowl of the toilet or water closet.
2. Description of the Prior Art
Usually, the above-mentioned part presents, towards the top of the cylindrical conduit through which the water contained in the flush tank is permitted to exit by gravitational flow to the bowl of the toilet, a surface which is hemispherical or frustroconical and closed in its bottom. As those skilled in the arts of the construction and the use of such equipment are well aware, no more than this is required in order to obtain an apparatus which is operable, affording, when the operating handle of the water closet is turned or the chain is pulled to take the part in question out of contact with the top of the conduit member in which it usually sits, a suitable downward rush of water under the influence of gravity through the conduit. The conduit is, at times between flushing operations, stoppered by the part or element in question.
Those skilled in the art should also be well aware, for example, from U.S. Pat. No. 1,904,898, that there has hitherto been known in the art the use of a valve member of frustroconical shape "preferably made of bronze or other rust-proof sheet metal", with the valve shown in the patent being one having a hollow interior and an open bottom.
The prior art contains, moreover, my earlier U.S. Pat. No. 4,385,406, which discloses a watercloset valve having two distinct seals located in a generally frustroconical portion of a rubber watercloset valve member which is adapted to be received within a matching frustroconical seat member located in the ceramic bottom of the flush tank of a water closet. The device there shown preferably relies upon circular 0-ring seals instead of having the parts of the valve that bring about the effect of the double seal comprises a pair of rubber ridges formed integrally in the rubber valve member. Moreover, the valve member there shown lacks the capability of affording the effect of causing the development of a partial vacuum within the hollow interior of the valve member as a result of the passage of water past the valve during the flushing action, and as a result, it does not provide any water-saving, accelerated closing action.